Preheat your oven to 325°F (160°C).
Season the short ribs generously with salt and pepper.
In a large Dutch oven, heat the vegetable oil over medium-high heat.
Sear the short ribs on all sides until well browned, about 3-4 minutes per side, then remove from the pot.
Add the onion, carrots, celery, and garlic to the pot. Sauté for about 5-7 minutes until softened.
Stir in the tomato paste and cook for an additional 2 minutes.
Pour in the red wine to deglaze the pot, scraping up any browned bits from the bottom.
Add the beef broth, thyme, bay leaves, and the seared short ribs back into the pot.
Bring the mixture to a simmer, then cover and transfer to the preheated oven.
Braize in the oven for 2.5 to 3 hours or until the meat is fork-tender.
Once cooked, remove the pot from the oven and let it rest before serving.
Remove the bay leaves and thyme sprigs before serving.